Publications

Makassar Strait and adjacent area have recently been targeted as an attractive new area for hydrocarbon exploration. Many geological and geophysical studies have been conducted, as a result of the discovery of numerous indications of the occurrence of petroleum, especially several oil seeps. Oil seeps were observed in the Paniki River, Kalukku, Mamuju, West Sulawesi Province. This oil seep is considered to have originated from Eocene coals or carbonaceous clays of the Toraja Formation. Petroleum geochemistry was then applied to this oil seep. This research is mainly focused on the degradation which is commonly encountered from oil in either subsurface or surface locations, a concern because the quality of oil deposits has been depleted to a certain degree. Identification was carried out using gas chromatography-mass spectrometry (GC-MS) analyses, with a selective ion monitoring (SIM) mode applied to the oil sample. GC-MS results reveal that the oil sample did indeed experience severe degradation. The absence of aromatic compounds was noted, which probably indicates water-washing processes encountered by the oil either inside a reservoir or during its migration to the surface. Isoprenoids are absent, while steranes, rearranged steranes and hopanes biomarkers have been degraded, possibly attacked by bacterial activity, indicating this oil sample experienced very heavy biodegradation (level 7-8).